Compilare: user.cpp:29:21: warning: multi-character character constant [-Wmultichar] if(i==-1) cout<<'-1'; ^ user.cpp: In function ‘int main()’: user.cpp:23:16: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen(In); ^ user.cpp:24:17: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen(Out); ^ user.cpp:25:19: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&n); ^ user.cpp:27:26: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&A[i]); ^